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Bilingual Seniors Have More Flexible Minds

Other than being able to speak more than one language, bilingualism may also provide a long-term cognitive benefit, according to a new study that found that older adults who have spoken two languages all their lives score higher on cognitive flexibility tasks than those who only spoke one language.

Researchers found that seniors who have spoken two languages since childhood are faster than their single language counterparts at switching from one task to another, according to a new study published Jan. 9 in The Journal of Neuroscience.

The latest findings also showed that lifelong bilinguals also showed different patterns of brain activity compared to their monolingual peers when asked to switch to a different task.

Scientists say that the findings highlight the value of regular stimulating activity across a person's lifetime. Researchers said that the mental boost seen in bilinguals might stem from the lifelong experience of constantly switching between languages.

Researchers explain that cognitive flexibility, or the ability to adapt to unfamiliar or unexpected circumstances, and other related "executive" functions declines as people age.

While recent findings have suggested that lifelong bilingualism may reduce this mental decline, the difference in brain activity between older bilinguals and monolinguals has been unclear, according to researchers involved in the latest study.

Brian Gold and his team at the University of Kentucky College of Medicine used functional magnetic resonance imaging to compare the brain activity of healthy bilingual seniors between the ages of 60 and 68 with their monolingual counterparts as they completed a cognitive flexibility task.

The findings revealed that while both groups performed the task accurately, bilingual seniors were significantly faster at completing the task than monolingual seniors despite using less energy in the frontal cortex, a region of the brain involved in task switching.

"This study provides some of the first evidence of an association between a particular cognitively stimulating activity - in this case, speaking multiple languages on a daily basis - and brain function," John Woodard, an aging expert from Wayne State University, who was not involved with the study, said in a statement.

"The authors provide clear evidence of a different pattern of neural functioning in bilingual versus monolingual individuals," he added.

Researchers also the measured the brain activity of younger bilingual and monolingual adults while they performed the cognitive flexibility tasks and found that while young adults were faster than seniors at performing the task, being bilingual did not affect task performance of brain activity in young participants.

"This suggests that bilingual seniors use their brains more efficiently than monolingual seniors," Gold said in a news release. "Together, these results suggest that lifelong bilingualism may exert its strongest benefits on the functioning of frontal brain regions in aging."